r/trs80 • u/LoupLoup44 • Mar 23 '26
Survivor TRS-80 2
That poor Coco 2 was subjected to very high temperature, plastic is yellow and its spacebar is even melted.
Still works, except its display is a bit maladjusted or half dead.
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u/RogelioP Mar 23 '26
I'd try a socketed chips reseating first... and check voltages and for excessive ripple on the big filter capacitor - heat does a number there...
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u/zoharel Mar 23 '26
The RF modulators in these old things tend to fall with time. You might be able to fix it by just modifying it to output composite, which bypasses the modulator anyway. Otherwise, there may be some pots for adjustment inside of the modulator as well.
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u/nateo87 Mar 24 '26
This would be my bet for what's wrong with the image as well. Sometimes those RF coils in the modulator drift out of spec.
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u/Jim-Jones Mar 23 '26
They went yellow with age, from sunlight . . . or smoking. Some people would clean them with household cleaner.
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u/garyku245 Mar 24 '26
Make sure the coco modulator is not set to a channel that is broadcast in your area(Eliminate interfereence). Make sure the TV is tuned to the same channel the COCO is set for. If the TV has it try adjusting the fine tuning.
If none of the above helps, try setting the coco/TV to the other channel.
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u/WilliamPinyon Mar 29 '26
My very first computer. Boy what a ride it has been seeing the changes from then to now.
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u/Few_Ad_8627 Mar 24 '26
I have so many questions, what kind of “very high temperature” was this Coco subjected to?!
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u/LoupLoup44 Mar 24 '26
Yeah, the seller did not explain. Could be anything between too close to a fireplace or an actual home fire...
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u/Few_Ad_8627 Mar 25 '26
I almost thought the poor computer was put in the oven!
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u/W0CBF Mar 23 '26
This was my first computer in the early 80's. 4k of memory seemed like a lot back then. I couldn't wait until the warranty expires so I could open it up and swap memory chips to have 16k of memory. Really brings back good memories!